Video Summary: Those who lack confidence may feel the deficiency is so in-grained as to surely be innate. In fact, confidence is something most of us are born with, before life steals it from us. You can recover the confidence you lost, or thought you never had.
The key is to start with introspection about the situations in which your lack of confidence becomes most pronounced. Try to identify the triggers for the issue, and notice the patterns in your present life.
Then think back to your youth or childhood. Who told you that you weren't good enough, or smart enough, or strong enough? What "limiting beliefs" did you adopt from those experiences? Have you learned to criticize yourself before anyone else has the chance? Do you crave other people's approval, even when telling others that you don't care what they think?
Positive affirmations, visualizations, mental rehearsal, plus bolstering body language, can make vast strides in building your store of confidence. Perhaps most important is to constantly stretch your comfort zone, a little at a time.
While success alone doesn't predict confidence, it certainly lubricates the process. Follow the steps in the recipe thoroughly and in the proper order to discover how much confidence you can grow.